package com.jqq.final_;

public class FinalExercise01 {
    public static void main(String[] args) {
        new Circle(5).getArea();
    }
}
class Circle{
    private double radius;
    private final double PI;
    public Circle(final double radius) {
//        PI = 3.14;
        this.radius = radius;
    }
    {
        PI = 3.14;
    }
    public void getArea(){
        System.out.println("radius="+radius+" 圆面积="+PI*radius*radius);
    }
}